The present invention relates to a stereoscopic television picture transmission system in which a stereoscopic television signal having compressed a frequency band is transmitted or recorded, and more particularly to a stereoscopic television picture transmission system for displaying a high definition television picture by performing subsampling with consideration being given to the time-frequency characteristic of the visual parallax sensed by a human being in the depth direction of a picture.
When an image having a three dimensional appearance is reproduced, two television signals corresponding to the fields of view of by the left and right eyes of a human being are required.
So far, in order to reproduce a three-dimensional image, it has been necessary to simultaneously transmit two video signals and to perform synchronous recording and reproduction by using two VTRs. However, the prior art system described above has a problem in terms of increased cost, since the transmission lines must be doubled and two VTRs must be additionally there are various disadvantages such as providing precision circuits and devising a transmission system for representing subtle parallax.
Therefore, in order to compress two stereoscopic television signals, corresponding to the right and left eyes, into a frequency band of the conventional one channel television signal for transmission there is proposed a system in which a difference signal that is, a parallax signal with respect to the right and left picture signals-is compressed for transmission by utilizing the degree of correlation between the right and left pictures. That is, parallax between the right and left pictures exists only in a near-distance view (for instance, an object within 10 meters from the cameras) and does not exist in the case of a long-distance view, so that the difference signal is produced only when parallax exists. Therefore, it is considered to compress and transmit the difference signal by effecting a time-axis compression of a time interval in which no parallax exists.
However, the difference signal originally includes many high frequency components of 1-2 MHz so that when the difference signal is compressed in the manner described above, the limitation of the differential signal band adversely affects the generation of a quality stereoscopic picture.